Growth hormone is important for normal growth and development in childhood. A lack of growth hormone in children is currently treated by human recombinant growth hormone that must be given daily by an injection under the skin. MK-0677 is a new drug which caused growth hormone release after oral administration. The purpose of this study is to evaluate the effectiveness of MK-0677 in increasing growth velocity in GH-deficient children; to evaluate the safety and tolerability of MK-0677; and to measure the release of GH and other hormones as well as MK-0677 blood levels following administration of MK-0677 to GH-deficient children. The present study will also assist in the selection of a dosage regimen for subsequent studies.